What is an invoice?

An invoice is a commercial document issued by a seller to a buyer, listing the goods or services provided, the amount due and the payment terms. It is simultaneously a request for payment, a record of a sale and — in most jurisdictions — a tax document.

The fields every invoice carries

• Seller identity: name, address and tax or registration number
• Customer identity: name, company and billing address
• Invoice number and issue date
• Due date or payment terms
• Line items: description, quantity, unit price
• Discounts, tax rates and tax amounts
• Grand total and how to pay

How an invoice moves through a business

You issue it, the customer's accounts payable team validates it against the purchase order, it enters a payment run, and the money arrives with the invoice number as reference. Your job is to make each of those steps frictionless: complete details, correct references and a clear total.

Why the details matter

An incomplete invoice is the single biggest cause of delayed payment. Missing tax numbers, mismatched purchase order references or unclear descriptions all give a reason to hold the invoice for another review cycle. A clean, consistent invoice shortens that cycle.